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1. Introduction

1.1 Why Linux?

You've heard that UNIX is difficult and balk at the prospect of leaving VMS, don't you? Don't worry. Linux, one of the finest UNIX clones, is not more difficult to use than VMS; actually, I find it easier. Although VMS aficionados may not agree, in many people's opinion Linux is much more powerful and versatile.

Linux and VMS are both good operating systems and accomplish essentially the same tasks, but Linux has a few features that make it a good alternative to VMS. Moreover, Linux is available for PCs while VMS is not, and modern Pentium-based Linux machines can outperform a VAX. The icing on the cake is the excellent performance of modern video cards, which turn an X11-based Linux box into a fast graphic workstation; nearly always, quicker than dedicated machines.

I imagine you're a university researcher or a student, and that you use VMS for the following everyday tasks:

  • writing papers with TeX/LaTeX;
  • programming in Fortran;
  • doing some graphics;
  • using Internet services;
  • et cetera.

In the following sections I'm going to explain to you how to do these tasks under Linux, exploiting your experience with VMS. Prerequisites:

  • Linux and X Window System are properly installed;
  • there's a system administrator to take care of the technical details (please get help from them, not from me ;-) ;
  • your shell---the equivalent of DCL---is bash (ask your sysadm).

Please note that this HOWTO is not enough to acquaint you fully with Linux: it only contains the bare essential to get you started. You should learn more about Linux to make the most of it (advanced bash features, programming, regular expressions...). From now on, RMP means `please read the man pages for further details'. The man pages are the equivalent of the command HELP.

The Linux Documentation Project documents, available on ftp://sunsite.unc.edu:/pub/Linux/docs/LDP, are an important source of information. I suggest that you read Larry Greenfield's ``Linux User Guide''---it's invaluable for the novice user.

And now, go ahead.

1.2 Comparing Commands and Files

This table attempts to compare VMS' and Linux' most used commands. Please keep in mind that the syntax is often very different; for more details, refer to the following sections.

VMS                             Linux                   Notes
------------------------------------------------------------------------------

@COMMAND                        command                 must be executable
COPY file1 file2                cp file1 file2
CREATE/DIR [.dirname]           mkdir dirname           only one at a time
CREATE/DIR [.dir1.dir2]         mkdirhier dir/name
DELETE filename                 rm filename
DIFF file1 file2                diff -c file1 file2
DIRECTORY                       ls
DIRECTORY [...]file             find . -name file
DIRECTORY/FULL                  ls -al
EDIT filename                   vi filename,            you won't like it
                                emacs filename,         EDT compatible
                                jed filename            ditto---my favourite
FORTRAN prog.for                g77 prog.f,             no need to do LINK
                                f77 prog.f,
                                fort77 prog.f
HELP command                    man command             must specify `command'
                                info command            ditto
LATEX file.tex                  latex file.tex
LOGIN.COM                       .bash_profile,          `hidden' file
                                .bashrc                 ditto
LOGOUT.COM                      .bash_logout            ditto
MAIL                            mail,                   crude
                                elm,                    much better
                                pine                    better still
PRINT file.ps                   lpr file.ps
PRINT/QUEUE=laser file.ps       lpr -Plaser file.ps
PHONE user                      talk user
RENAME file1 file2              mv file1 file2          not for multiple files
RUN progname                    progname
SEARCH file "pattern"           grep pattern file
SET DEFAULT [-]                 cd ..
SET DEFAULT [.dir.name]         cd dir/name
SET HOST hostname               telnet hostname,        not exactly the same
                                rlogin hostname
SET FILE/OWNER_UIC=joe          chown joe file          completely different
SET NOBROADCAST                 mesg
SET PASSWORD                    passwd
SET PROT=(perm) file            chmod perm file         completely different
SET TERMINAL                    export TERM=            different syntax
SHOW DEFAULT                    pwd
SHOW DEVICE                     du, df
SHOW ENTRY                      lpq
SHOW PROCESS                    ps -ax
SHOW QUEUE                      lpq
SHOW SYSTEM                     top
SHOW TIME                       date
SHOW USERS                      w
STOP                            kill
STOP/QUEUE                      kill,                   for processes
                                lprm                    for print queues
SUBMIT command                  command &
SUBMIT/AFTER=time command       at time command
TEX file.tex                    tex file.tex
TYPE/PAGE file                  more file
                                less file               much better

But of course it's not only a matter of different command names. Read on.


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